Is it bad for the car if I put it in neutral when going down a long, steep hill?

[psteng19]

On the highway where I commute daily, a portion of it is a steep hill (about a mile or so long) and there's always stop-and-go traffic during rush hour.
Instead of putting the car in gear, I'll just leave it in neutral and let gravity pull me down the hill, brake when necessary.
I figure there shouldn't be any damage to the drivetrain and less wear on the clutch.
But I think I read somewhere that said it's bad to be in neutral while the car is moving for extended periods of time.

 

[oogabooga]

I don't think anything bad happens to your car, but i'm not 100% sure

If you're in california, it's actually illegal to coast in a vehicle in neutral i believe.. *shrugs* as to why, but apparently it is.

 

[kevman]

it will probably have some effect on your brakes, since while you are in gear when you brake the engine kinda helps the car slow down as the RPM's come down

 

[The Stigenator]

As a rule, never coast in neutral..i have always been told that by my dad. He has a permernent german licence.

 

[Mo0o]

I think it wears out your brakes more.

 

[jagec]

It's not bad for your car, but it does cause a bit more wear on your brakes since there's no engine braking.

Why would it save your clutch? The ONLY time the clutch gets worn is when you're engaging or disengaging it (primarily when engaging it).

So unless you revmatch before putting it back in gear at the end of the hill, you're actually wearing the clutch down MORE. Not much more, of course.

The only real time when it's necessary/helpful to coast in neutral is when you're out of gas and going down a hill to the nearest station.

 

[spidey07]

I'm not a mechanic but I can't see it as being a good thing because your synchros/synchro bearings would be spinning like crazy. So the wear would be on the transmission, cluth/flywheel would have nothing to do with it as they are already engaged - no wear on the clutch.

Again, I'm NOT a mechanic nor do I profess to know the intimate workings of a transmission...its just my best guess.

So I'm thinking synchros.

 

[Brutuskend]

Probably not, but it IS illegal in most if not ALL states.

 

[psteng19]

I'm not too worried about brakes because this is in heavy traffic where I only inch forward a few feet at a time.

It would save my clutch because I don't have to engage the clutch at all.
Just neutral and brake, etc.

Can someone elaborate on what spidey mentioned about synchros, if it is true?

 

[blurredvision]

Another vote for no from a non-mechanic, non-car person. I've always heard it's bad to do this.

 

[spidey07]

Originally posted by: psteng19
I'm not too worried about brakes because this is in heavy traffic where I only inch forward a few feet at a time.

It would save my clutch because I don't have to engage the clutch at all.
Just neutral and brake, etc.

Can someone elaborate on what spidey mentioned about synchros, if it is true?

heh, I'm waiting for somebody that knows what they're talking about to respond as well.



When in neutral your transmission is still spinning. You have the input side of your tranny spinning at idle and the other side (the wheel side) going 70 MPH. Somethings gotta be taking excessive wear from the mis-matched speeds.

 

[jagec]

Originally posted by: spidey07
I'm not a mechanic but I can't see it as being a good thing because your synchros/synchro bearings would be spinning like crazy. So the wear would be on the transmission, cluth/flywheel would have nothing to do with it as they are already engaged - no wear on the clutch.

Again, I'm NOT a mechanic nor do I profess to know the intimate workings of a transmission...its just my best guess.

So I'm thinking synchros.

When the shifter is in neutral and the engine is idling, the gears ain't spinning too fast. Now, having the shifter in a low gear while holding down the clutch pedal...

Originally posted by: psteng19
I'm not too worried about brakes because this is in heavy traffic where I only inch forward a few feet at a time.

It would save my clutch because I don't have to engage the clutch at all.
Just neutral and brake, etc.

Can someone elaborate on what spidey mentioned about synchros, if it is true?

Ah, that makes more sense. In heavy traffic, like you mention, there is nothing wrong with keeping it in neutral and just using the brake.

Don't worry about the synchro thing.

 

[Brutuskend]

The reason it's illegal is when your tranny is engaged it controls your speed somewhat. Relying on the brakes alone can cause them to over heat and fade/fail.

 

[jagec]

Originally posted by: Brutuskend
The reason it's illegal is when your tranny is engaged it controls your speed somewhat. Relying on the brakes alone can cause them to over heat and fade/fail.

Yeah, but the guy's talking about stop-and-go traffic. If his traffic is anything like mine, that's 0-15 mph max. Sitting in neutral is OK in that situation.

 

[JulesMaximus]

Originally posted by: psteng19
I'm not too worried about brakes because this is in heavy traffic where I only inch forward a few feet at a time.

It would save my clutch because I don't have to engage the clutch at all.
Just neutral and brake, etc.

Can someone elaborate on what spidey mentioned about synchros, if it is true?

No big deal. Don't worry about it.

If you were regularly cruising down 2-3 mile long hills in neutral at 50-60 miles an hour then yeah, that would be a bad thing.

 

[AgaBoogaBoo]

That sounds like it won't be a problem because of the low speed you're driving at

You only need to worry about staying in gear downhill if you're going a long distance at higher speeds, otherwise your brakes pads should be fine.

 

[0roo0roo]

not sure i see the point. the engine is spinning either way. i think this was answered on cartalk.com or the radioshow. engine might work harder to keep running with no load.

 

[psteng19]

Originally posted by: JulesMaximus

Originally posted by: psteng19
I'm not too worried about brakes because this is in heavy traffic where I only inch forward a few feet at a time.

It would save my clutch because I don't have to engage the clutch at all.
Just neutral and brake, etc.

Can someone elaborate on what spidey mentioned about synchros, if it is true?

No big deal. Don't worry about it.

If you were regularly cruising down 2-3 mile long hills in neutral at 50-60 miles an hour then yeah, that would be a bad thing.

Other than brakes heating up and not having control over the car because it's not in gear, is there a mechanical reason why going 50 mph in neutral would be bad?

Originally posted by: 0roo0roo
not sure i see the point. the engine is spinning either way. i think this was answered on cartalk.com or the radioshow. engine might work harder to keep running with no load.

It's not to save gas or anything. It's to save my left leg from clutching in and out.

 

[Howard]

I'm pretty sure the synchromeshes *aren't* engaged when in neutral.

 

[jagec]

Originally posted by: 0roo0roo
not sure i see the point. the engine is spinning either way. i think this was answered on cartalk.com or the radioshow. engine might work harder to keep running with no load.

in stop-and-go traffic down a hill, it's just pointless to keep engaging and disengaging the clutch. Might as well just leave it in neutral and let gravity do the work. And fuel economy is darn near 0 either way.

 

[JulesMaximus]

Originally posted by: psteng19

Originally posted by: JulesMaximus

Originally posted by: psteng19
I'm not too worried about brakes because this is in heavy traffic where I only inch forward a few feet at a time.

It would save my clutch because I don't have to engage the clutch at all.
Just neutral and brake, etc.

Can someone elaborate on what spidey mentioned about synchros, if it is true?

No big deal. Don't worry about it.

If you were regularly cruising down 2-3 mile long hills in neutral at 50-60 miles an hour then yeah, that would be a bad thing.

Other than brakes heating up and not having control over the car because it's not in gear, is there a mechanical reason why going 50 mph in neutral would be bad?

I have no idea. I do know that it is bad to tow rear wheel drive cars with the driven wheels on the ground though. Not sure if this has anything to do with the topic at hand though. Sorry...wish Roger was here to enlighten us though.

 

[0roo0roo]

Dear Tom and Ray:

I'm a woman with a new Ford Ranger XLT. I have four idiotic brothers who tell me it's bad to coast down hills in Neutral. Help me prove these men WRONG!! -- Karen

Tom: They're right, Karen. They probably were wrong to make you taste frogs [bluecar.gif] when you were a kid ... and to tell you that you were adopted from space aliens, but they're right about coasting down hills.

Ray: Coasting downhill is dangerous for several reasons. First of all, without the natural braking action of the engine, you can pick up a lot of speed in a hurry.

Tom: And in that situation, to keep from going too fast, you're likely to overuse and overheat your brakes.

Ray: And overheating the brakes is no small matter. When they overheat, the brake fluid can actually start to boil. And when the brake fluid boils, your pedal goes right to the floor.

Tom: You also might need to make an emergency maneuver and accelerate to get out of somebody's way. And if you're in Neutral, it'll take you longer to do that -- maybe too long.

Ray: And finally, when you're coasting, the engine could stall without your knowing it -- until you tried to stop or turn and found you had no power steering or power brakes.

Tom: And as Homer Simpson would say at that point, Karen: "Doh!"
http://www.cartalk.com/content...1996/September/05.html

 

[jagec]

Originally posted by: 0roo0roo

Tom: And in that situation, to keep from going too fast, you're likely to overuse and overheat your brakes.

Ray: And overheating the brakes is no small matter. When they overheat, the brake fluid can actually start to boil. And when the brake fluid boils, your pedal goes right to the floor.

Tom: You also might need to make an emergency maneuver and accelerate to get out of somebody's way. And if you're in Neutral, it'll take you longer to do that -- maybe too long.

Ray: And finally, when you're coasting, the engine could stall without your knowing it -- until you tried to stop or turn and found you had no power steering or power brakes.

So as long as you don't ride the brakes, watch your surroundings, and don't have an unreliable car, you're fine.

Granted, that's more than most people are willing to do...so for the most part coasting is BAD.

 

[OS]

Originally posted by: spidey07
I'm not a mechanic but I can't see it as being a good thing because your synchros/synchro bearings would be spinning like crazy. So the wear would be on the transmission, cluth/flywheel would have nothing to do with it as they are already engaged - no wear on the clutch.

Again, I'm NOT a mechanic nor do I profess to know the intimate workings of a transmission...its just my best guess.

So I'm thinking synchros.

The drive shafts, synchros, whatever else aren't going to spin any faster in neutral than if they were in gear for any given speed. The driveshaft/axle, gears, wheels are all physically tied together and the gear ratios are also fixed.

 

[Barnaby W. Füi]

I don't get the "control" argument. At a higher speed, you can't accelerate super fast in the current gear anyway. You'd need to downshift. If you don't even have enough time to shift once, then the current gear probably isn't going to provide enough acceleration either. Right?